1 // SPDX-License-Identifier: LGPL-2.1 2 /* 3 * 4 * Copyright (C) International Business Machines Corp., 2002,2008 5 * Author(s): Steve French (sfrench@us.ibm.com) 6 * 7 */ 8 9 #include <linux/slab.h> 10 #include <linux/ctype.h> 11 #include <linux/mempool.h> 12 #include <linux/vmalloc.h> 13 #include "cifspdu.h" 14 #include "cifsglob.h" 15 #include "cifsproto.h" 16 #include "cifs_debug.h" 17 #include "smberr.h" 18 #include "nterr.h" 19 #include "cifs_unicode.h" 20 #include "smb2pdu.h" 21 #include "cifsfs.h" 22 #ifdef CONFIG_CIFS_DFS_UPCALL 23 #include "dns_resolve.h" 24 #include "dfs_cache.h" 25 #include "dfs.h" 26 #endif 27 #include "fs_context.h" 28 #include "cached_dir.h" 29 30 /* The xid serves as a useful identifier for each incoming vfs request, 31 in a similar way to the mid which is useful to track each sent smb, 32 and CurrentXid can also provide a running counter (although it 33 will eventually wrap past zero) of the total vfs operations handled 34 since the cifs fs was mounted */ 35 36 unsigned int 37 _get_xid(void) 38 { 39 unsigned int xid; 40 41 spin_lock(&GlobalMid_Lock); 42 GlobalTotalActiveXid++; 43 44 /* keep high water mark for number of simultaneous ops in filesystem */ 45 if (GlobalTotalActiveXid > GlobalMaxActiveXid) 46 GlobalMaxActiveXid = GlobalTotalActiveXid; 47 if (GlobalTotalActiveXid > 65000) 48 cifs_dbg(FYI, "warning: more than 65000 requests active\n"); 49 xid = GlobalCurrentXid++; 50 spin_unlock(&GlobalMid_Lock); 51 return xid; 52 } 53 54 void 55 _free_xid(unsigned int xid) 56 { 57 spin_lock(&GlobalMid_Lock); 58 /* if (GlobalTotalActiveXid == 0) 59 BUG(); */ 60 GlobalTotalActiveXid--; 61 spin_unlock(&GlobalMid_Lock); 62 } 63 64 struct cifs_ses * 65 sesInfoAlloc(void) 66 { 67 struct cifs_ses *ret_buf; 68 69 ret_buf = kzalloc(sizeof(struct cifs_ses), GFP_KERNEL); 70 if (ret_buf) { 71 atomic_inc(&sesInfoAllocCount); 72 spin_lock_init(&ret_buf->ses_lock); 73 ret_buf->ses_status = SES_NEW; 74 ++ret_buf->ses_count; 75 INIT_LIST_HEAD(&ret_buf->smb_ses_list); 76 INIT_LIST_HEAD(&ret_buf->tcon_list); 77 mutex_init(&ret_buf->session_mutex); 78 spin_lock_init(&ret_buf->iface_lock); 79 INIT_LIST_HEAD(&ret_buf->iface_list); 80 spin_lock_init(&ret_buf->chan_lock); 81 } 82 return ret_buf; 83 } 84 85 void 86 sesInfoFree(struct cifs_ses *buf_to_free) 87 { 88 struct cifs_server_iface *iface = NULL, *niface = NULL; 89 90 if (buf_to_free == NULL) { 91 cifs_dbg(FYI, "Null buffer passed to sesInfoFree\n"); 92 return; 93 } 94 95 unload_nls(buf_to_free->local_nls); 96 atomic_dec(&sesInfoAllocCount); 97 kfree(buf_to_free->serverOS); 98 kfree(buf_to_free->serverDomain); 99 kfree(buf_to_free->serverNOS); 100 kfree_sensitive(buf_to_free->password); 101 kfree_sensitive(buf_to_free->password2); 102 kfree(buf_to_free->user_name); 103 kfree(buf_to_free->domainName); 104 kfree(buf_to_free->dns_dom); 105 kfree_sensitive(buf_to_free->auth_key.response); 106 spin_lock(&buf_to_free->iface_lock); 107 list_for_each_entry_safe(iface, niface, &buf_to_free->iface_list, 108 iface_head) 109 kref_put(&iface->refcount, release_iface); 110 spin_unlock(&buf_to_free->iface_lock); 111 kfree_sensitive(buf_to_free); 112 } 113 114 struct cifs_tcon * 115 tcon_info_alloc(bool dir_leases_enabled, enum smb3_tcon_ref_trace trace) 116 { 117 struct cifs_tcon *ret_buf; 118 static atomic_t tcon_debug_id; 119 120 ret_buf = kzalloc(sizeof(*ret_buf), GFP_KERNEL); 121 if (!ret_buf) 122 return NULL; 123 124 if (dir_leases_enabled == true) { 125 ret_buf->cfids = init_cached_dirs(); 126 if (!ret_buf->cfids) { 127 kfree(ret_buf); 128 return NULL; 129 } 130 } 131 /* else ret_buf->cfids is already set to NULL above */ 132 133 atomic_inc(&tconInfoAllocCount); 134 ret_buf->status = TID_NEW; 135 ret_buf->debug_id = atomic_inc_return(&tcon_debug_id); 136 ret_buf->tc_count = 1; 137 spin_lock_init(&ret_buf->tc_lock); 138 INIT_LIST_HEAD(&ret_buf->openFileList); 139 INIT_LIST_HEAD(&ret_buf->tcon_list); 140 INIT_LIST_HEAD(&ret_buf->cifs_sb_list); 141 spin_lock_init(&ret_buf->open_file_lock); 142 spin_lock_init(&ret_buf->stat_lock); 143 spin_lock_init(&ret_buf->sb_list_lock); 144 atomic_set(&ret_buf->num_local_opens, 0); 145 atomic_set(&ret_buf->num_remote_opens, 0); 146 ret_buf->stats_from_time = ktime_get_real_seconds(); 147 #ifdef CONFIG_CIFS_FSCACHE 148 mutex_init(&ret_buf->fscache_lock); 149 #endif 150 trace_smb3_tcon_ref(ret_buf->debug_id, ret_buf->tc_count, trace); 151 #ifdef CONFIG_CIFS_DFS_UPCALL 152 INIT_LIST_HEAD(&ret_buf->dfs_ses_list); 153 #endif 154 155 return ret_buf; 156 } 157 158 void 159 tconInfoFree(struct cifs_tcon *tcon, enum smb3_tcon_ref_trace trace) 160 { 161 if (tcon == NULL) { 162 cifs_dbg(FYI, "Null buffer passed to tconInfoFree\n"); 163 return; 164 } 165 trace_smb3_tcon_ref(tcon->debug_id, tcon->tc_count, trace); 166 free_cached_dirs(tcon->cfids); 167 atomic_dec(&tconInfoAllocCount); 168 kfree(tcon->nativeFileSystem); 169 kfree_sensitive(tcon->password); 170 kfree(tcon->origin_fullpath); 171 kfree(tcon); 172 } 173 174 struct smb_hdr * 175 cifs_buf_get(void) 176 { 177 struct smb_hdr *ret_buf = NULL; 178 /* 179 * SMB2 header is bigger than CIFS one - no problems to clean some 180 * more bytes for CIFS. 181 */ 182 size_t buf_size = sizeof(struct smb2_hdr); 183 184 /* 185 * We could use negotiated size instead of max_msgsize - 186 * but it may be more efficient to always alloc same size 187 * albeit slightly larger than necessary and maxbuffersize 188 * defaults to this and can not be bigger. 189 */ 190 ret_buf = mempool_alloc(cifs_req_poolp, GFP_NOFS); 191 192 /* clear the first few header bytes */ 193 /* for most paths, more is cleared in header_assemble */ 194 memset(ret_buf, 0, buf_size + 3); 195 atomic_inc(&buf_alloc_count); 196 #ifdef CONFIG_CIFS_STATS2 197 atomic_inc(&total_buf_alloc_count); 198 #endif /* CONFIG_CIFS_STATS2 */ 199 200 return ret_buf; 201 } 202 203 void 204 cifs_buf_release(void *buf_to_free) 205 { 206 if (buf_to_free == NULL) { 207 /* cifs_dbg(FYI, "Null buffer passed to cifs_buf_release\n");*/ 208 return; 209 } 210 mempool_free(buf_to_free, cifs_req_poolp); 211 212 atomic_dec(&buf_alloc_count); 213 return; 214 } 215 216 struct smb_hdr * 217 cifs_small_buf_get(void) 218 { 219 struct smb_hdr *ret_buf = NULL; 220 221 /* We could use negotiated size instead of max_msgsize - 222 but it may be more efficient to always alloc same size 223 albeit slightly larger than necessary and maxbuffersize 224 defaults to this and can not be bigger */ 225 ret_buf = mempool_alloc(cifs_sm_req_poolp, GFP_NOFS); 226 /* No need to clear memory here, cleared in header assemble */ 227 /* memset(ret_buf, 0, sizeof(struct smb_hdr) + 27);*/ 228 atomic_inc(&small_buf_alloc_count); 229 #ifdef CONFIG_CIFS_STATS2 230 atomic_inc(&total_small_buf_alloc_count); 231 #endif /* CONFIG_CIFS_STATS2 */ 232 233 return ret_buf; 234 } 235 236 void 237 cifs_small_buf_release(void *buf_to_free) 238 { 239 240 if (buf_to_free == NULL) { 241 cifs_dbg(FYI, "Null buffer passed to cifs_small_buf_release\n"); 242 return; 243 } 244 mempool_free(buf_to_free, cifs_sm_req_poolp); 245 246 atomic_dec(&small_buf_alloc_count); 247 return; 248 } 249 250 void 251 free_rsp_buf(int resp_buftype, void *rsp) 252 { 253 if (resp_buftype == CIFS_SMALL_BUFFER) 254 cifs_small_buf_release(rsp); 255 else if (resp_buftype == CIFS_LARGE_BUFFER) 256 cifs_buf_release(rsp); 257 } 258 259 /* NB: MID can not be set if treeCon not passed in, in that 260 case it is responsibility of caller to set the mid */ 261 void 262 header_assemble(struct smb_hdr *buffer, char smb_command /* command */ , 263 const struct cifs_tcon *treeCon, int word_count 264 /* length of fixed section (word count) in two byte units */) 265 { 266 char *temp = (char *) buffer; 267 268 memset(temp, 0, 256); /* bigger than MAX_CIFS_HDR_SIZE */ 269 270 buffer->smb_buf_length = cpu_to_be32( 271 (2 * word_count) + sizeof(struct smb_hdr) - 272 4 /* RFC 1001 length field does not count */ + 273 2 /* for bcc field itself */) ; 274 275 buffer->Protocol[0] = 0xFF; 276 buffer->Protocol[1] = 'S'; 277 buffer->Protocol[2] = 'M'; 278 buffer->Protocol[3] = 'B'; 279 buffer->Command = smb_command; 280 buffer->Flags = 0x00; /* case sensitive */ 281 buffer->Flags2 = SMBFLG2_KNOWS_LONG_NAMES; 282 buffer->Pid = cpu_to_le16((__u16)current->tgid); 283 buffer->PidHigh = cpu_to_le16((__u16)(current->tgid >> 16)); 284 if (treeCon) { 285 buffer->Tid = treeCon->tid; 286 if (treeCon->ses) { 287 if (treeCon->ses->capabilities & CAP_UNICODE) 288 buffer->Flags2 |= SMBFLG2_UNICODE; 289 if (treeCon->ses->capabilities & CAP_STATUS32) 290 buffer->Flags2 |= SMBFLG2_ERR_STATUS; 291 292 /* Uid is not converted */ 293 buffer->Uid = treeCon->ses->Suid; 294 if (treeCon->ses->server) 295 buffer->Mid = get_next_mid(treeCon->ses->server); 296 } 297 if (treeCon->Flags & SMB_SHARE_IS_IN_DFS) 298 buffer->Flags2 |= SMBFLG2_DFS; 299 if (treeCon->nocase) 300 buffer->Flags |= SMBFLG_CASELESS; 301 if ((treeCon->ses) && (treeCon->ses->server)) 302 if (treeCon->ses->server->sign) 303 buffer->Flags2 |= SMBFLG2_SECURITY_SIGNATURE; 304 } 305 306 /* endian conversion of flags is now done just before sending */ 307 buffer->WordCount = (char) word_count; 308 return; 309 } 310 311 static int 312 check_smb_hdr(struct smb_hdr *smb) 313 { 314 /* does it have the right SMB "signature" ? */ 315 if (*(__le32 *) smb->Protocol != cpu_to_le32(0x424d53ff)) { 316 cifs_dbg(VFS, "Bad protocol string signature header 0x%x\n", 317 *(unsigned int *)smb->Protocol); 318 return 1; 319 } 320 321 /* if it's a response then accept */ 322 if (smb->Flags & SMBFLG_RESPONSE) 323 return 0; 324 325 /* only one valid case where server sends us request */ 326 if (smb->Command == SMB_COM_LOCKING_ANDX) 327 return 0; 328 329 cifs_dbg(VFS, "Server sent request, not response. mid=%u\n", 330 get_mid(smb)); 331 return 1; 332 } 333 334 int 335 checkSMB(char *buf, unsigned int total_read, struct TCP_Server_Info *server) 336 { 337 struct smb_hdr *smb = (struct smb_hdr *)buf; 338 __u32 rfclen = be32_to_cpu(smb->smb_buf_length); 339 __u32 clc_len; /* calculated length */ 340 cifs_dbg(FYI, "checkSMB Length: 0x%x, smb_buf_length: 0x%x\n", 341 total_read, rfclen); 342 343 /* is this frame too small to even get to a BCC? */ 344 if (total_read < 2 + sizeof(struct smb_hdr)) { 345 if ((total_read >= sizeof(struct smb_hdr) - 1) 346 && (smb->Status.CifsError != 0)) { 347 /* it's an error return */ 348 smb->WordCount = 0; 349 /* some error cases do not return wct and bcc */ 350 return 0; 351 } else if ((total_read == sizeof(struct smb_hdr) + 1) && 352 (smb->WordCount == 0)) { 353 char *tmp = (char *)smb; 354 /* Need to work around a bug in two servers here */ 355 /* First, check if the part of bcc they sent was zero */ 356 if (tmp[sizeof(struct smb_hdr)] == 0) { 357 /* some servers return only half of bcc 358 * on simple responses (wct, bcc both zero) 359 * in particular have seen this on 360 * ulogoffX and FindClose. This leaves 361 * one byte of bcc potentially uninitialized 362 */ 363 /* zero rest of bcc */ 364 tmp[sizeof(struct smb_hdr)+1] = 0; 365 return 0; 366 } 367 cifs_dbg(VFS, "rcvd invalid byte count (bcc)\n"); 368 } else { 369 cifs_dbg(VFS, "Length less than smb header size\n"); 370 } 371 return -EIO; 372 } else if (total_read < sizeof(*smb) + 2 * smb->WordCount) { 373 cifs_dbg(VFS, "%s: can't read BCC due to invalid WordCount(%u)\n", 374 __func__, smb->WordCount); 375 return -EIO; 376 } 377 378 /* otherwise, there is enough to get to the BCC */ 379 if (check_smb_hdr(smb)) 380 return -EIO; 381 clc_len = smbCalcSize(smb); 382 383 if (4 + rfclen != total_read) { 384 cifs_dbg(VFS, "Length read does not match RFC1001 length %d\n", 385 rfclen); 386 return -EIO; 387 } 388 389 if (4 + rfclen != clc_len) { 390 __u16 mid = get_mid(smb); 391 /* check if bcc wrapped around for large read responses */ 392 if ((rfclen > 64 * 1024) && (rfclen > clc_len)) { 393 /* check if lengths match mod 64K */ 394 if (((4 + rfclen) & 0xFFFF) == (clc_len & 0xFFFF)) 395 return 0; /* bcc wrapped */ 396 } 397 cifs_dbg(FYI, "Calculated size %u vs length %u mismatch for mid=%u\n", 398 clc_len, 4 + rfclen, mid); 399 400 if (4 + rfclen < clc_len) { 401 cifs_dbg(VFS, "RFC1001 size %u smaller than SMB for mid=%u\n", 402 rfclen, mid); 403 return -EIO; 404 } else if (rfclen > clc_len + 512) { 405 /* 406 * Some servers (Windows XP in particular) send more 407 * data than the lengths in the SMB packet would 408 * indicate on certain calls (byte range locks and 409 * trans2 find first calls in particular). While the 410 * client can handle such a frame by ignoring the 411 * trailing data, we choose limit the amount of extra 412 * data to 512 bytes. 413 */ 414 cifs_dbg(VFS, "RFC1001 size %u more than 512 bytes larger than SMB for mid=%u\n", 415 rfclen, mid); 416 return -EIO; 417 } 418 } 419 return 0; 420 } 421 422 bool 423 is_valid_oplock_break(char *buffer, struct TCP_Server_Info *srv) 424 { 425 struct smb_hdr *buf = (struct smb_hdr *)buffer; 426 struct smb_com_lock_req *pSMB = (struct smb_com_lock_req *)buf; 427 struct TCP_Server_Info *pserver; 428 struct cifs_ses *ses; 429 struct cifs_tcon *tcon; 430 struct cifsInodeInfo *pCifsInode; 431 struct cifsFileInfo *netfile; 432 433 cifs_dbg(FYI, "Checking for oplock break or dnotify response\n"); 434 if ((pSMB->hdr.Command == SMB_COM_NT_TRANSACT) && 435 (pSMB->hdr.Flags & SMBFLG_RESPONSE)) { 436 struct smb_com_transaction_change_notify_rsp *pSMBr = 437 (struct smb_com_transaction_change_notify_rsp *)buf; 438 struct file_notify_information *pnotify; 439 __u32 data_offset = 0; 440 size_t len = srv->total_read - sizeof(pSMBr->hdr.smb_buf_length); 441 442 if (get_bcc(buf) > sizeof(struct file_notify_information)) { 443 data_offset = le32_to_cpu(pSMBr->DataOffset); 444 445 if (data_offset > 446 len - sizeof(struct file_notify_information)) { 447 cifs_dbg(FYI, "Invalid data_offset %u\n", 448 data_offset); 449 return true; 450 } 451 pnotify = (struct file_notify_information *) 452 ((char *)&pSMBr->hdr.Protocol + data_offset); 453 cifs_dbg(FYI, "dnotify on %s Action: 0x%x\n", 454 pnotify->FileName, pnotify->Action); 455 /* cifs_dump_mem("Rcvd notify Data: ",buf, 456 sizeof(struct smb_hdr)+60); */ 457 return true; 458 } 459 if (pSMBr->hdr.Status.CifsError) { 460 cifs_dbg(FYI, "notify err 0x%x\n", 461 pSMBr->hdr.Status.CifsError); 462 return true; 463 } 464 return false; 465 } 466 if (pSMB->hdr.Command != SMB_COM_LOCKING_ANDX) 467 return false; 468 if (pSMB->hdr.Flags & SMBFLG_RESPONSE) { 469 /* no sense logging error on invalid handle on oplock 470 break - harmless race between close request and oplock 471 break response is expected from time to time writing out 472 large dirty files cached on the client */ 473 if ((NT_STATUS_INVALID_HANDLE) == 474 le32_to_cpu(pSMB->hdr.Status.CifsError)) { 475 cifs_dbg(FYI, "Invalid handle on oplock break\n"); 476 return true; 477 } else if (ERRbadfid == 478 le16_to_cpu(pSMB->hdr.Status.DosError.Error)) { 479 return true; 480 } else { 481 return false; /* on valid oplock brk we get "request" */ 482 } 483 } 484 if (pSMB->hdr.WordCount != 8) 485 return false; 486 487 cifs_dbg(FYI, "oplock type 0x%x level 0x%x\n", 488 pSMB->LockType, pSMB->OplockLevel); 489 if (!(pSMB->LockType & LOCKING_ANDX_OPLOCK_RELEASE)) 490 return false; 491 492 /* If server is a channel, select the primary channel */ 493 pserver = SERVER_IS_CHAN(srv) ? srv->primary_server : srv; 494 495 /* look up tcon based on tid & uid */ 496 spin_lock(&cifs_tcp_ses_lock); 497 list_for_each_entry(ses, &pserver->smb_ses_list, smb_ses_list) { 498 if (cifs_ses_exiting(ses)) 499 continue; 500 list_for_each_entry(tcon, &ses->tcon_list, tcon_list) { 501 if (tcon->tid != buf->Tid) 502 continue; 503 504 cifs_stats_inc(&tcon->stats.cifs_stats.num_oplock_brks); 505 spin_lock(&tcon->open_file_lock); 506 list_for_each_entry(netfile, &tcon->openFileList, tlist) { 507 if (pSMB->Fid != netfile->fid.netfid) 508 continue; 509 510 cifs_dbg(FYI, "file id match, oplock break\n"); 511 pCifsInode = CIFS_I(d_inode(netfile->dentry)); 512 513 set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK, 514 &pCifsInode->flags); 515 516 netfile->oplock_epoch = 0; 517 netfile->oplock_level = pSMB->OplockLevel; 518 netfile->oplock_break_cancelled = false; 519 cifs_queue_oplock_break(netfile); 520 521 spin_unlock(&tcon->open_file_lock); 522 spin_unlock(&cifs_tcp_ses_lock); 523 return true; 524 } 525 spin_unlock(&tcon->open_file_lock); 526 spin_unlock(&cifs_tcp_ses_lock); 527 cifs_dbg(FYI, "No matching file for oplock break\n"); 528 return true; 529 } 530 } 531 spin_unlock(&cifs_tcp_ses_lock); 532 cifs_dbg(FYI, "Can not process oplock break for non-existent connection\n"); 533 return true; 534 } 535 536 void 537 dump_smb(void *buf, int smb_buf_length) 538 { 539 if (traceSMB == 0) 540 return; 541 542 print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_NONE, 8, 2, buf, 543 smb_buf_length, true); 544 } 545 546 void 547 cifs_autodisable_serverino(struct cifs_sb_info *cifs_sb) 548 { 549 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM) { 550 struct cifs_tcon *tcon = NULL; 551 552 if (cifs_sb->master_tlink) 553 tcon = cifs_sb_master_tcon(cifs_sb); 554 555 cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_SERVER_INUM; 556 cifs_sb->mnt_cifs_serverino_autodisabled = true; 557 cifs_dbg(VFS, "Autodisabling the use of server inode numbers on %s\n", 558 tcon ? tcon->tree_name : "new server"); 559 cifs_dbg(VFS, "The server doesn't seem to support them properly or the files might be on different servers (DFS)\n"); 560 cifs_dbg(VFS, "Hardlinks will not be recognized on this mount. Consider mounting with the \"noserverino\" option to silence this message.\n"); 561 562 } 563 } 564 565 void cifs_set_oplock_level(struct cifsInodeInfo *cinode, __u32 oplock) 566 { 567 oplock &= 0xF; 568 569 if (oplock == OPLOCK_EXCLUSIVE) { 570 cinode->oplock = CIFS_CACHE_WRITE_FLG | CIFS_CACHE_READ_FLG; 571 cifs_dbg(FYI, "Exclusive Oplock granted on inode %p\n", 572 &cinode->netfs.inode); 573 } else if (oplock == OPLOCK_READ) { 574 cinode->oplock = CIFS_CACHE_READ_FLG; 575 cifs_dbg(FYI, "Level II Oplock granted on inode %p\n", 576 &cinode->netfs.inode); 577 } else 578 cinode->oplock = 0; 579 } 580 581 /* 582 * We wait for oplock breaks to be processed before we attempt to perform 583 * writes. 584 */ 585 int cifs_get_writer(struct cifsInodeInfo *cinode) 586 { 587 int rc; 588 589 start: 590 rc = wait_on_bit(&cinode->flags, CIFS_INODE_PENDING_OPLOCK_BREAK, 591 TASK_KILLABLE); 592 if (rc) 593 return rc; 594 595 spin_lock(&cinode->writers_lock); 596 if (!cinode->writers) 597 set_bit(CIFS_INODE_PENDING_WRITERS, &cinode->flags); 598 cinode->writers++; 599 /* Check to see if we have started servicing an oplock break */ 600 if (test_bit(CIFS_INODE_PENDING_OPLOCK_BREAK, &cinode->flags)) { 601 cinode->writers--; 602 if (cinode->writers == 0) { 603 clear_bit(CIFS_INODE_PENDING_WRITERS, &cinode->flags); 604 wake_up_bit(&cinode->flags, CIFS_INODE_PENDING_WRITERS); 605 } 606 spin_unlock(&cinode->writers_lock); 607 goto start; 608 } 609 spin_unlock(&cinode->writers_lock); 610 return 0; 611 } 612 613 void cifs_put_writer(struct cifsInodeInfo *cinode) 614 { 615 spin_lock(&cinode->writers_lock); 616 cinode->writers--; 617 if (cinode->writers == 0) { 618 clear_bit(CIFS_INODE_PENDING_WRITERS, &cinode->flags); 619 wake_up_bit(&cinode->flags, CIFS_INODE_PENDING_WRITERS); 620 } 621 spin_unlock(&cinode->writers_lock); 622 } 623 624 /** 625 * cifs_queue_oplock_break - queue the oplock break handler for cfile 626 * @cfile: The file to break the oplock on 627 * 628 * This function is called from the demultiplex thread when it 629 * receives an oplock break for @cfile. 630 * 631 * Assumes the tcon->open_file_lock is held. 632 * Assumes cfile->file_info_lock is NOT held. 633 */ 634 void cifs_queue_oplock_break(struct cifsFileInfo *cfile) 635 { 636 /* 637 * Bump the handle refcount now while we hold the 638 * open_file_lock to enforce the validity of it for the oplock 639 * break handler. The matching put is done at the end of the 640 * handler. 641 */ 642 cifsFileInfo_get(cfile); 643 644 queue_work(cifsoplockd_wq, &cfile->oplock_break); 645 } 646 647 void cifs_done_oplock_break(struct cifsInodeInfo *cinode) 648 { 649 clear_bit(CIFS_INODE_PENDING_OPLOCK_BREAK, &cinode->flags); 650 wake_up_bit(&cinode->flags, CIFS_INODE_PENDING_OPLOCK_BREAK); 651 } 652 653 bool 654 backup_cred(struct cifs_sb_info *cifs_sb) 655 { 656 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_CIFS_BACKUPUID) { 657 if (uid_eq(cifs_sb->ctx->backupuid, current_fsuid())) 658 return true; 659 } 660 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_CIFS_BACKUPGID) { 661 if (in_group_p(cifs_sb->ctx->backupgid)) 662 return true; 663 } 664 665 return false; 666 } 667 668 void 669 cifs_del_pending_open(struct cifs_pending_open *open) 670 { 671 spin_lock(&tlink_tcon(open->tlink)->open_file_lock); 672 list_del(&open->olist); 673 spin_unlock(&tlink_tcon(open->tlink)->open_file_lock); 674 } 675 676 void 677 cifs_add_pending_open_locked(struct cifs_fid *fid, struct tcon_link *tlink, 678 struct cifs_pending_open *open) 679 { 680 memcpy(open->lease_key, fid->lease_key, SMB2_LEASE_KEY_SIZE); 681 open->oplock = CIFS_OPLOCK_NO_CHANGE; 682 open->tlink = tlink; 683 fid->pending_open = open; 684 list_add_tail(&open->olist, &tlink_tcon(tlink)->pending_opens); 685 } 686 687 void 688 cifs_add_pending_open(struct cifs_fid *fid, struct tcon_link *tlink, 689 struct cifs_pending_open *open) 690 { 691 spin_lock(&tlink_tcon(tlink)->open_file_lock); 692 cifs_add_pending_open_locked(fid, tlink, open); 693 spin_unlock(&tlink_tcon(open->tlink)->open_file_lock); 694 } 695 696 /* 697 * Critical section which runs after acquiring deferred_lock. 698 * As there is no reference count on cifs_deferred_close, pdclose 699 * should not be used outside deferred_lock. 700 */ 701 bool 702 cifs_is_deferred_close(struct cifsFileInfo *cfile, struct cifs_deferred_close **pdclose) 703 { 704 struct cifs_deferred_close *dclose; 705 706 list_for_each_entry(dclose, &CIFS_I(d_inode(cfile->dentry))->deferred_closes, dlist) { 707 if ((dclose->netfid == cfile->fid.netfid) && 708 (dclose->persistent_fid == cfile->fid.persistent_fid) && 709 (dclose->volatile_fid == cfile->fid.volatile_fid)) { 710 *pdclose = dclose; 711 return true; 712 } 713 } 714 return false; 715 } 716 717 /* 718 * Critical section which runs after acquiring deferred_lock. 719 */ 720 void 721 cifs_add_deferred_close(struct cifsFileInfo *cfile, struct cifs_deferred_close *dclose) 722 { 723 bool is_deferred = false; 724 struct cifs_deferred_close *pdclose; 725 726 is_deferred = cifs_is_deferred_close(cfile, &pdclose); 727 if (is_deferred) { 728 kfree(dclose); 729 return; 730 } 731 732 dclose->tlink = cfile->tlink; 733 dclose->netfid = cfile->fid.netfid; 734 dclose->persistent_fid = cfile->fid.persistent_fid; 735 dclose->volatile_fid = cfile->fid.volatile_fid; 736 list_add_tail(&dclose->dlist, &CIFS_I(d_inode(cfile->dentry))->deferred_closes); 737 } 738 739 /* 740 * Critical section which runs after acquiring deferred_lock. 741 */ 742 void 743 cifs_del_deferred_close(struct cifsFileInfo *cfile) 744 { 745 bool is_deferred = false; 746 struct cifs_deferred_close *dclose; 747 748 is_deferred = cifs_is_deferred_close(cfile, &dclose); 749 if (!is_deferred) 750 return; 751 list_del(&dclose->dlist); 752 kfree(dclose); 753 } 754 755 void 756 cifs_close_deferred_file(struct cifsInodeInfo *cifs_inode) 757 { 758 struct cifsFileInfo *cfile = NULL; 759 struct file_list *tmp_list, *tmp_next_list; 760 LIST_HEAD(file_head); 761 762 if (cifs_inode == NULL) 763 return; 764 765 spin_lock(&cifs_inode->open_file_lock); 766 list_for_each_entry(cfile, &cifs_inode->openFileList, flist) { 767 if (delayed_work_pending(&cfile->deferred)) { 768 if (cancel_delayed_work(&cfile->deferred)) { 769 spin_lock(&cifs_inode->deferred_lock); 770 cifs_del_deferred_close(cfile); 771 spin_unlock(&cifs_inode->deferred_lock); 772 773 tmp_list = kmalloc(sizeof(struct file_list), GFP_ATOMIC); 774 if (tmp_list == NULL) 775 break; 776 tmp_list->cfile = cfile; 777 list_add_tail(&tmp_list->list, &file_head); 778 } 779 } 780 } 781 spin_unlock(&cifs_inode->open_file_lock); 782 783 list_for_each_entry_safe(tmp_list, tmp_next_list, &file_head, list) { 784 _cifsFileInfo_put(tmp_list->cfile, false, false); 785 list_del(&tmp_list->list); 786 kfree(tmp_list); 787 } 788 } 789 790 void 791 cifs_close_all_deferred_files(struct cifs_tcon *tcon) 792 { 793 struct cifsFileInfo *cfile; 794 struct file_list *tmp_list, *tmp_next_list; 795 LIST_HEAD(file_head); 796 797 spin_lock(&tcon->open_file_lock); 798 list_for_each_entry(cfile, &tcon->openFileList, tlist) { 799 if (delayed_work_pending(&cfile->deferred)) { 800 if (cancel_delayed_work(&cfile->deferred)) { 801 spin_lock(&CIFS_I(d_inode(cfile->dentry))->deferred_lock); 802 cifs_del_deferred_close(cfile); 803 spin_unlock(&CIFS_I(d_inode(cfile->dentry))->deferred_lock); 804 805 tmp_list = kmalloc(sizeof(struct file_list), GFP_ATOMIC); 806 if (tmp_list == NULL) 807 break; 808 tmp_list->cfile = cfile; 809 list_add_tail(&tmp_list->list, &file_head); 810 } 811 } 812 } 813 spin_unlock(&tcon->open_file_lock); 814 815 list_for_each_entry_safe(tmp_list, tmp_next_list, &file_head, list) { 816 _cifsFileInfo_put(tmp_list->cfile, true, false); 817 list_del(&tmp_list->list); 818 kfree(tmp_list); 819 } 820 } 821 void 822 cifs_close_deferred_file_under_dentry(struct cifs_tcon *tcon, const char *path) 823 { 824 struct cifsFileInfo *cfile; 825 struct file_list *tmp_list, *tmp_next_list; 826 void *page; 827 const char *full_path; 828 LIST_HEAD(file_head); 829 830 page = alloc_dentry_path(); 831 spin_lock(&tcon->open_file_lock); 832 list_for_each_entry(cfile, &tcon->openFileList, tlist) { 833 full_path = build_path_from_dentry(cfile->dentry, page); 834 if (strstr(full_path, path)) { 835 if (delayed_work_pending(&cfile->deferred)) { 836 if (cancel_delayed_work(&cfile->deferred)) { 837 spin_lock(&CIFS_I(d_inode(cfile->dentry))->deferred_lock); 838 cifs_del_deferred_close(cfile); 839 spin_unlock(&CIFS_I(d_inode(cfile->dentry))->deferred_lock); 840 841 tmp_list = kmalloc(sizeof(struct file_list), GFP_ATOMIC); 842 if (tmp_list == NULL) 843 break; 844 tmp_list->cfile = cfile; 845 list_add_tail(&tmp_list->list, &file_head); 846 } 847 } 848 } 849 } 850 spin_unlock(&tcon->open_file_lock); 851 852 list_for_each_entry_safe(tmp_list, tmp_next_list, &file_head, list) { 853 _cifsFileInfo_put(tmp_list->cfile, true, false); 854 list_del(&tmp_list->list); 855 kfree(tmp_list); 856 } 857 free_dentry_path(page); 858 } 859 860 /* 861 * If a dentry has been deleted, all corresponding open handles should know that 862 * so that we do not defer close them. 863 */ 864 void cifs_mark_open_handles_for_deleted_file(struct inode *inode, 865 const char *path) 866 { 867 struct cifsFileInfo *cfile; 868 void *page; 869 const char *full_path; 870 struct cifsInodeInfo *cinode = CIFS_I(inode); 871 872 page = alloc_dentry_path(); 873 spin_lock(&cinode->open_file_lock); 874 875 /* 876 * note: we need to construct path from dentry and compare only if the 877 * inode has any hardlinks. When number of hardlinks is 1, we can just 878 * mark all open handles since they are going to be from the same file. 879 */ 880 if (inode->i_nlink > 1) { 881 list_for_each_entry(cfile, &cinode->openFileList, flist) { 882 full_path = build_path_from_dentry(cfile->dentry, page); 883 if (!IS_ERR(full_path) && strcmp(full_path, path) == 0) 884 cfile->status_file_deleted = true; 885 } 886 } else { 887 list_for_each_entry(cfile, &cinode->openFileList, flist) 888 cfile->status_file_deleted = true; 889 } 890 spin_unlock(&cinode->open_file_lock); 891 free_dentry_path(page); 892 } 893 894 /* parses DFS referral V3 structure 895 * caller is responsible for freeing target_nodes 896 * returns: 897 * - on success - 0 898 * - on failure - errno 899 */ 900 int 901 parse_dfs_referrals(struct get_dfs_referral_rsp *rsp, u32 rsp_size, 902 unsigned int *num_of_nodes, 903 struct dfs_info3_param **target_nodes, 904 const struct nls_table *nls_codepage, int remap, 905 const char *searchName, bool is_unicode) 906 { 907 int i, rc = 0; 908 char *data_end; 909 struct dfs_referral_level_3 *ref; 910 911 *num_of_nodes = le16_to_cpu(rsp->NumberOfReferrals); 912 913 if (*num_of_nodes < 1) { 914 cifs_dbg(VFS | ONCE, "%s: [path=%s] num_referrals must be at least > 0, but we got %d\n", 915 __func__, searchName, *num_of_nodes); 916 rc = -ENOENT; 917 goto parse_DFS_referrals_exit; 918 } 919 920 ref = (struct dfs_referral_level_3 *) &(rsp->referrals); 921 if (ref->VersionNumber != cpu_to_le16(3)) { 922 cifs_dbg(VFS, "Referrals of V%d version are not supported, should be V3\n", 923 le16_to_cpu(ref->VersionNumber)); 924 rc = -EINVAL; 925 goto parse_DFS_referrals_exit; 926 } 927 928 /* get the upper boundary of the resp buffer */ 929 data_end = (char *)rsp + rsp_size; 930 931 cifs_dbg(FYI, "num_referrals: %d dfs flags: 0x%x ...\n", 932 *num_of_nodes, le32_to_cpu(rsp->DFSFlags)); 933 934 *target_nodes = kcalloc(*num_of_nodes, sizeof(struct dfs_info3_param), 935 GFP_KERNEL); 936 if (*target_nodes == NULL) { 937 rc = -ENOMEM; 938 goto parse_DFS_referrals_exit; 939 } 940 941 /* collect necessary data from referrals */ 942 for (i = 0; i < *num_of_nodes; i++) { 943 char *temp; 944 int max_len; 945 struct dfs_info3_param *node = (*target_nodes)+i; 946 947 node->flags = le32_to_cpu(rsp->DFSFlags); 948 if (is_unicode) { 949 __le16 *tmp = kmalloc(strlen(searchName)*2 + 2, 950 GFP_KERNEL); 951 if (tmp == NULL) { 952 rc = -ENOMEM; 953 goto parse_DFS_referrals_exit; 954 } 955 cifsConvertToUTF16((__le16 *) tmp, searchName, 956 PATH_MAX, nls_codepage, remap); 957 node->path_consumed = cifs_utf16_bytes(tmp, 958 le16_to_cpu(rsp->PathConsumed), 959 nls_codepage); 960 kfree(tmp); 961 } else 962 node->path_consumed = le16_to_cpu(rsp->PathConsumed); 963 964 node->server_type = le16_to_cpu(ref->ServerType); 965 node->ref_flag = le16_to_cpu(ref->ReferralEntryFlags); 966 967 /* copy DfsPath */ 968 temp = (char *)ref + le16_to_cpu(ref->DfsPathOffset); 969 max_len = data_end - temp; 970 node->path_name = cifs_strndup_from_utf16(temp, max_len, 971 is_unicode, nls_codepage); 972 if (!node->path_name) { 973 rc = -ENOMEM; 974 goto parse_DFS_referrals_exit; 975 } 976 977 /* copy link target UNC */ 978 temp = (char *)ref + le16_to_cpu(ref->NetworkAddressOffset); 979 max_len = data_end - temp; 980 node->node_name = cifs_strndup_from_utf16(temp, max_len, 981 is_unicode, nls_codepage); 982 if (!node->node_name) { 983 rc = -ENOMEM; 984 goto parse_DFS_referrals_exit; 985 } 986 987 node->ttl = le32_to_cpu(ref->TimeToLive); 988 989 ref++; 990 } 991 992 parse_DFS_referrals_exit: 993 if (rc) { 994 free_dfs_info_array(*target_nodes, *num_of_nodes); 995 *target_nodes = NULL; 996 *num_of_nodes = 0; 997 } 998 return rc; 999 } 1000 1001 /** 1002 * cifs_alloc_hash - allocate hash and hash context together 1003 * @name: The name of the crypto hash algo 1004 * @sdesc: SHASH descriptor where to put the pointer to the hash TFM 1005 * 1006 * The caller has to make sure @sdesc is initialized to either NULL or 1007 * a valid context. It can be freed via cifs_free_hash(). 1008 */ 1009 int 1010 cifs_alloc_hash(const char *name, struct shash_desc **sdesc) 1011 { 1012 int rc = 0; 1013 struct crypto_shash *alg = NULL; 1014 1015 if (*sdesc) 1016 return 0; 1017 1018 alg = crypto_alloc_shash(name, 0, 0); 1019 if (IS_ERR(alg)) { 1020 cifs_dbg(VFS, "Could not allocate shash TFM '%s'\n", name); 1021 rc = PTR_ERR(alg); 1022 *sdesc = NULL; 1023 return rc; 1024 } 1025 1026 *sdesc = kmalloc(sizeof(struct shash_desc) + crypto_shash_descsize(alg), GFP_KERNEL); 1027 if (*sdesc == NULL) { 1028 cifs_dbg(VFS, "no memory left to allocate shash TFM '%s'\n", name); 1029 crypto_free_shash(alg); 1030 return -ENOMEM; 1031 } 1032 1033 (*sdesc)->tfm = alg; 1034 return 0; 1035 } 1036 1037 /** 1038 * cifs_free_hash - free hash and hash context together 1039 * @sdesc: Where to find the pointer to the hash TFM 1040 * 1041 * Freeing a NULL descriptor is safe. 1042 */ 1043 void 1044 cifs_free_hash(struct shash_desc **sdesc) 1045 { 1046 if (unlikely(!sdesc) || !*sdesc) 1047 return; 1048 1049 if ((*sdesc)->tfm) { 1050 crypto_free_shash((*sdesc)->tfm); 1051 (*sdesc)->tfm = NULL; 1052 } 1053 1054 kfree_sensitive(*sdesc); 1055 *sdesc = NULL; 1056 } 1057 1058 void extract_unc_hostname(const char *unc, const char **h, size_t *len) 1059 { 1060 const char *end; 1061 1062 /* skip initial slashes */ 1063 while (*unc && (*unc == '\\' || *unc == '/')) 1064 unc++; 1065 1066 end = unc; 1067 1068 while (*end && !(*end == '\\' || *end == '/')) 1069 end++; 1070 1071 *h = unc; 1072 *len = end - unc; 1073 } 1074 1075 /** 1076 * copy_path_name - copy src path to dst, possibly truncating 1077 * @dst: The destination buffer 1078 * @src: The source name 1079 * 1080 * returns number of bytes written (including trailing nul) 1081 */ 1082 int copy_path_name(char *dst, const char *src) 1083 { 1084 int name_len; 1085 1086 /* 1087 * PATH_MAX includes nul, so if strlen(src) >= PATH_MAX it 1088 * will truncate and strlen(dst) will be PATH_MAX-1 1089 */ 1090 name_len = strscpy(dst, src, PATH_MAX); 1091 if (WARN_ON_ONCE(name_len < 0)) 1092 name_len = PATH_MAX-1; 1093 1094 /* we count the trailing nul */ 1095 name_len++; 1096 return name_len; 1097 } 1098 1099 struct super_cb_data { 1100 void *data; 1101 struct super_block *sb; 1102 }; 1103 1104 static void tcon_super_cb(struct super_block *sb, void *arg) 1105 { 1106 struct super_cb_data *sd = arg; 1107 struct cifs_sb_info *cifs_sb; 1108 struct cifs_tcon *t1 = sd->data, *t2; 1109 1110 if (sd->sb) 1111 return; 1112 1113 cifs_sb = CIFS_SB(sb); 1114 t2 = cifs_sb_master_tcon(cifs_sb); 1115 1116 spin_lock(&t2->tc_lock); 1117 if ((t1->ses == t2->ses || 1118 t1->ses->dfs_root_ses == t2->ses->dfs_root_ses) && 1119 t1->ses->server == t2->ses->server && 1120 t2->origin_fullpath && 1121 dfs_src_pathname_equal(t2->origin_fullpath, t1->origin_fullpath)) 1122 sd->sb = sb; 1123 spin_unlock(&t2->tc_lock); 1124 } 1125 1126 static struct super_block *__cifs_get_super(void (*f)(struct super_block *, void *), 1127 void *data) 1128 { 1129 struct super_cb_data sd = { 1130 .data = data, 1131 .sb = NULL, 1132 }; 1133 struct file_system_type **fs_type = (struct file_system_type *[]) { 1134 &cifs_fs_type, &smb3_fs_type, NULL, 1135 }; 1136 1137 for (; *fs_type; fs_type++) { 1138 iterate_supers_type(*fs_type, f, &sd); 1139 if (sd.sb) { 1140 /* 1141 * Grab an active reference in order to prevent automounts (DFS links) 1142 * of expiring and then freeing up our cifs superblock pointer while 1143 * we're doing failover. 1144 */ 1145 cifs_sb_active(sd.sb); 1146 return sd.sb; 1147 } 1148 } 1149 pr_warn_once("%s: could not find dfs superblock\n", __func__); 1150 return ERR_PTR(-EINVAL); 1151 } 1152 1153 static void __cifs_put_super(struct super_block *sb) 1154 { 1155 if (!IS_ERR_OR_NULL(sb)) 1156 cifs_sb_deactive(sb); 1157 } 1158 1159 struct super_block *cifs_get_dfs_tcon_super(struct cifs_tcon *tcon) 1160 { 1161 spin_lock(&tcon->tc_lock); 1162 if (!tcon->origin_fullpath) { 1163 spin_unlock(&tcon->tc_lock); 1164 return ERR_PTR(-ENOENT); 1165 } 1166 spin_unlock(&tcon->tc_lock); 1167 return __cifs_get_super(tcon_super_cb, tcon); 1168 } 1169 1170 void cifs_put_tcp_super(struct super_block *sb) 1171 { 1172 __cifs_put_super(sb); 1173 } 1174 1175 #ifdef CONFIG_CIFS_DFS_UPCALL 1176 int match_target_ip(struct TCP_Server_Info *server, 1177 const char *host, size_t hostlen, 1178 bool *result) 1179 { 1180 struct sockaddr_storage ss; 1181 int rc; 1182 1183 cifs_dbg(FYI, "%s: hostname=%.*s\n", __func__, (int)hostlen, host); 1184 1185 *result = false; 1186 1187 rc = dns_resolve_name(server->dns_dom, host, hostlen, 1188 (struct sockaddr *)&ss); 1189 if (rc < 0) 1190 return rc; 1191 1192 spin_lock(&server->srv_lock); 1193 *result = cifs_match_ipaddr((struct sockaddr *)&server->dstaddr, (struct sockaddr *)&ss); 1194 spin_unlock(&server->srv_lock); 1195 cifs_dbg(FYI, "%s: ip addresses matched: %s\n", __func__, str_yes_no(*result)); 1196 return 0; 1197 } 1198 1199 int cifs_update_super_prepath(struct cifs_sb_info *cifs_sb, char *prefix) 1200 { 1201 int rc; 1202 1203 kfree(cifs_sb->prepath); 1204 cifs_sb->prepath = NULL; 1205 1206 if (prefix && *prefix) { 1207 cifs_sb->prepath = cifs_sanitize_prepath(prefix, GFP_ATOMIC); 1208 if (IS_ERR(cifs_sb->prepath)) { 1209 rc = PTR_ERR(cifs_sb->prepath); 1210 cifs_sb->prepath = NULL; 1211 return rc; 1212 } 1213 if (cifs_sb->prepath) 1214 convert_delimiter(cifs_sb->prepath, CIFS_DIR_SEP(cifs_sb)); 1215 } 1216 1217 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH; 1218 return 0; 1219 } 1220 1221 /* 1222 * Handle weird Windows SMB server behaviour. It responds with 1223 * STATUS_OBJECT_NAME_INVALID code to SMB2 QUERY_INFO request for 1224 * "\<server>\<dfsname>\<linkpath>" DFS reference, where <dfsname> contains 1225 * non-ASCII unicode symbols. 1226 */ 1227 int cifs_inval_name_dfs_link_error(const unsigned int xid, 1228 struct cifs_tcon *tcon, 1229 struct cifs_sb_info *cifs_sb, 1230 const char *full_path, 1231 bool *islink) 1232 { 1233 struct TCP_Server_Info *server = tcon->ses->server; 1234 struct cifs_ses *ses = tcon->ses; 1235 size_t len; 1236 char *path; 1237 char *ref_path; 1238 1239 *islink = false; 1240 1241 /* 1242 * Fast path - skip check when @full_path doesn't have a prefix path to 1243 * look up or tcon is not DFS. 1244 */ 1245 if (strlen(full_path) < 2 || !cifs_sb || 1246 (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_DFS) || 1247 !is_tcon_dfs(tcon)) 1248 return 0; 1249 1250 spin_lock(&server->srv_lock); 1251 if (!server->leaf_fullpath) { 1252 spin_unlock(&server->srv_lock); 1253 return 0; 1254 } 1255 spin_unlock(&server->srv_lock); 1256 1257 /* 1258 * Slow path - tcon is DFS and @full_path has prefix path, so attempt 1259 * to get a referral to figure out whether it is an DFS link. 1260 */ 1261 len = strnlen(tcon->tree_name, MAX_TREE_SIZE + 1) + strlen(full_path) + 1; 1262 path = kmalloc(len, GFP_KERNEL); 1263 if (!path) 1264 return -ENOMEM; 1265 1266 scnprintf(path, len, "%s%s", tcon->tree_name, full_path); 1267 ref_path = dfs_cache_canonical_path(path + 1, cifs_sb->local_nls, 1268 cifs_remap(cifs_sb)); 1269 kfree(path); 1270 1271 if (IS_ERR(ref_path)) { 1272 if (PTR_ERR(ref_path) != -EINVAL) 1273 return PTR_ERR(ref_path); 1274 } else { 1275 struct dfs_info3_param *refs = NULL; 1276 int num_refs = 0; 1277 1278 /* 1279 * XXX: we are not using dfs_cache_find() here because we might 1280 * end up filling all the DFS cache and thus potentially 1281 * removing cached DFS targets that the client would eventually 1282 * need during failover. 1283 */ 1284 ses = CIFS_DFS_ROOT_SES(ses); 1285 if (ses->server->ops->get_dfs_refer && 1286 !ses->server->ops->get_dfs_refer(xid, ses, ref_path, &refs, 1287 &num_refs, cifs_sb->local_nls, 1288 cifs_remap(cifs_sb))) 1289 *islink = refs[0].server_type == DFS_TYPE_LINK; 1290 free_dfs_info_array(refs, num_refs); 1291 kfree(ref_path); 1292 } 1293 return 0; 1294 } 1295 #endif 1296 1297 int cifs_wait_for_server_reconnect(struct TCP_Server_Info *server, bool retry) 1298 { 1299 int timeout = 10; 1300 int rc; 1301 1302 spin_lock(&server->srv_lock); 1303 if (server->tcpStatus != CifsNeedReconnect) { 1304 spin_unlock(&server->srv_lock); 1305 return 0; 1306 } 1307 timeout *= server->nr_targets; 1308 spin_unlock(&server->srv_lock); 1309 1310 /* 1311 * Give demultiplex thread up to 10 seconds to each target available for 1312 * reconnect -- should be greater than cifs socket timeout which is 7 1313 * seconds. 1314 * 1315 * On "soft" mounts we wait once. Hard mounts keep retrying until 1316 * process is killed or server comes back on-line. 1317 */ 1318 do { 1319 rc = wait_event_interruptible_timeout(server->response_q, 1320 (server->tcpStatus != CifsNeedReconnect), 1321 timeout * HZ); 1322 if (rc < 0) { 1323 cifs_dbg(FYI, "%s: aborting reconnect due to received signal\n", 1324 __func__); 1325 return -ERESTARTSYS; 1326 } 1327 1328 /* are we still trying to reconnect? */ 1329 spin_lock(&server->srv_lock); 1330 if (server->tcpStatus != CifsNeedReconnect) { 1331 spin_unlock(&server->srv_lock); 1332 return 0; 1333 } 1334 spin_unlock(&server->srv_lock); 1335 } while (retry); 1336 1337 cifs_dbg(FYI, "%s: gave up waiting on reconnect\n", __func__); 1338 return -EHOSTDOWN; 1339 } 1340